Last week, the Supreme Court heard oral argument in Massachusetts v. EPA, which presents the question of whether the Environmental Protection Agency (EPA) violated the Clean Air Act by failing to regulate emissions of carbon dioxide and other greenhouse gases by motor vehicles in the United States.

The stakes could not be higher. A recent British study estimated the likely economic costs from global warming to be on the scale of those of the Great Depression or the First or Second World War. Yet U.S. auto emissions account for only about six percent of human-generated greenhouse gases escaping into the atmosphere, so that even a radical reduction--say, by half--would have no effect on 97 percent of human-generated greenhouse gases. Thus, the Bush Administration has argued, regulation by the EPA without international coordination, will simply impose domestic costs without substantial benefits.

Who makes the better case? Don't count on the Supreme Court to provide an answer. Roughly half of last week's oral argument focused not on whether the EPA violated its legal duty in failing to promulgate regulations, but instead on whether Massachusetts and other states have legal standing to seek judicial review of the EPA's inaction,. A decision dismissing the case on standing grounds is a real possibility.

A better result would be to revise the standing doctrine itself. As this case well illustrates, it imposes unnecessary obstacles to judicial resolution of very important legal questions.

shall by regulation prescribe (and from time to time revise) … standards applicable to the emission of any air pollutant from any class or classes of new motor vehicles or new motor vehicle engines, which in [its] judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare.

Massachusetts and the other petitioners argue that the law mandates regulation of carbon dioxide. Given the scientific consensus that human-generated greenhouse gases in the atmosphere contribute to global warming, which in turn will likely lead to coastal flooding and a host of other ills, such gases plainly "endanger public health or welfare," thus triggering an obligation to regulate: The law says the EPA "shall" prescribe standards, not that it "may" prescribe them.

The EPA under the Bush Administration disagrees. Although their predecessors under the Clinton Administration concluded that the agency had authority to regulate carbon dioxide emissions from new motor vehicles, the current regulators issued an August 2003 memo reaching the opposite conclusion. That memo argues that carbon dioxide is not a "pollutant" within the meaning of the Clean Air Act.

According to the memo, which was echoed by the Administration in its brief and during the oral argument, pollutants, within the meaning of the Clean Air Act, themselves harm public health or welfare, and do so locally. By contrast, carbon dioxide in the lower atmosphere is essentially harmless, and the damage it does by trapping heat in the troposphere is not localized. Although this argument may well capture the overall intent of Congress, it does seem to contradict the wording of the Clean Air Act itself, which does not expressly require that pollutants be harmful in themselves or that they act locally.

On the merits, the case would likely be decided by the Justices' choice of analogy. The Bush Administration places substantial reliance on the Court's 2000 decision in FDA v. Brown & Williamson. The Food, Drug, and Cosmetic Act authorizes the Food and Drug Administration to regulate "drugs" and "devices," which would seem to encompass regulation of the drug nicotine delivered by the device of cigarettes. But in Brown and Williamson, the Court rejected this literal parsing of the statutory text, in part on the ground that other statutes indicated that Congress had chosen to regulate tobacco products through other means.

Sotoo here, the government argues that Congress has chosen to address threats to the upper atmosphere through specific legislation, as in the case of stratospheric ozone. The Clean Air Act's mandate of regulation, the Administration therefore contends, does not apply.

Massachusetts and the other petitioners counter with a different analogy: Acid rain, they note, is an indirect, non-local result of substances emitted by cars (and stationary sources); yet the EPA has been understood to have the authority to curb sulfur dioxide and nitrogen oxides in order to reduce acid rain. Accordingly, they argue that the literal reading of the Clean Air Act is the best reading.

The Standing Doctrine

Who's right? Should the Court reach the merits of the case, not only will it have to choose the better analogy; it will also have to make a preliminary determination as to whether the EPA's decision not to regulate greenhouse gas emissions is entitled to the deference that the Court usually accords to the decisions of an administrative agency charged by Congress with implementing a statute. Thus, the merits of Massachusetts v. EPA are not clear-cut.

But the Court may well duck the merits. Supreme Court cases require that a plaintiff suing in federal court must have standing. Where does this requirement come from? Article III of the Constitution empowers federal courts to hear "Cases" and "Controversies," and the Court interprets these words to require an actual live dispute, as opposed to a hypothetical question that seeks a merely advisory opinion.

Where the plaintiff demands monetary damages for a completed harm, the Article III standing requirement is easily satisfied. Thus, most of the cases exploring the limits of Article III standing have involved suits for injunctions--orders that the defendant take, or refrain from taking, some action to avoid future harm.

The standing rules that the Supreme Court has located in the case-or-controversy requirement are complex, but three requirements stand out as particularly strange in a case like Massachusetts v. EPA. The plaintiff must show: first, that the injury alleged by the plaintiff is imminent; second, that the alleged injury is "concrete and particularized," rather than a "generalized grievance;" and third, that it is "likely," rather than merely "speculative," that the alleged injury will be redressed by a favorable judgment. Let us briefly consider these requirements in turn.

The Requirement of Imminence

There are circumstances in which the requirement that the threatened injury be imminent contributes to a proper limitation of federal court jurisdiction. If, for example, the government or a private party has threatened to take some adverse action years in the future, then adjudicating the dispute today may be unnecessary. Perhaps the potential defendant will have a change of heart long before the threatened harm occurs, and litigation can be avoided.

But the imminence requirement--if understood to bar Massachusetts from litigating now--makes no sense in the context of a phenomenon like global warming. As greenhouse gases build in the troposphere, they trap more and more heat at the Earth's surface, leading eventually to severe damage to ecosystems on which human well-being depends. Although Massachusetts Assistant Attorney General James Milkey gamely argued to the Court that the harmful effects of global warming have already begun to be felt, there is no sensible reason that he should have been required to so argue.

Many phenomena are non-linear; that is to say, each small change leads to no discernible difference until a tipping point is reached, after which dramatic change ensues. Warming itself provides a familiar example. A block of ice slowly heated from 29 degrees Fahrenheit, to 30 degrees, to 31 degrees appears largely unchanged, until it hits 32 degrees, at which point it begins to melt.

To the extent that global warming works in a similar fashion, waiting for cataclysmic change to be imminent may mean waiting to take action until the action taken will likely accomplish far too little to avoid the harm. Massachusetts and the other petitioners have made at least a colorable showing that further EPA failure to take action now will decrease the likelihood that it can take effective measures later. It is a strange doctrine indeed that says that such a showing does not at least constitute a case or controversy.

The Requirement of Particularization

Like the imminence requirement, the particularization requirement of standing doctrine has roots in sensible judgments about the proper respective roles of courts and legislatures. However, also like the imminence requirement, the particularization requirement can be perverse, as Massachusetts v. EPA demonstrates.

The Court's cases forbid plaintiffs from bringing "generalized" grievances to court because such matters should be taken to Congress or the state legislatures. The core prohibition on generalized grievances concerns circumstances in which a plaintiff merely disagrees with government policy. For example, let's say I am unhappy that the Administration has authorized warrantless wiretapping. Even though I can plausibly allege that such wiretapping violates the Foreign Intelligence Surveillance Act, I can't bring a lawsuit to complain about the policy unless I have a colorable claim that the government has intercepted my own conversations. My contention that it pains me to live in a country where the Executive violates the law is not enough.

Putting aside the difficulty that people whose communications have been illicitly monitored often won't be aware of that fact, if we really do have a case of someone complaining about nothing other than the violation of the law in the abstract--perhaps I don't have a telephone, or don't make or receive international calls--there is something to be said for denying standing. But unfortunately, the Court's cases have sometimes gone much further, and required that even a plaintiff who has suffered a personal injury as the result of allegedly unlawful conduct by the defendant must also show that his personal injury is different in some way from personal injuries suffered by other prospective plaintiffs.

The global warming case is a good example. During the oral argument, several Justices asked Mr. Milkey whether, under his theory of the case, a small landowner whose beachfront property was being claimed by rising seas would have standing to sue the EPA. Although they did not make the point expressly, these questions suggested that there may be a problem for Massachusetts because it's complaining about too much harm. Under the particularization requirement, the courts sometimes deny standing to challenge government action on the ground that the allegedly unlawful action causes injury to everybody. That is quite a lot to pack into the Constitution's use of the terms "Cases" and "Controversies."

The Requirement of Redressability

The Supreme Court's standing rules also require that a plaintiff show that a favorable ruling is "likely" to redress the injury. Here too, we can see a rationale for a modest version of this requirement. For example, a plaintiff who complains that he is imprisoned for a crime he did not commit, but seeks as a remedy his transfer from a maximum security prison to a medium or minimum security one, really does present a hypothetical case: the remedy bears no logical relation to the alleged unlawful conduct.

Unfortunately, the Court's redressability cases sometimes impose much stricter limits. For example, in the 1984 case of Allen v. Wright, the Court denied standing to African-American plaintiffs who challenged what they regarded as insufficient efforts by the Internal Revenue Service to deny tax-exempt status to racially discriminatory schools. Such lax enforcement, the plaintiffs argued, amounted to a de facto subsidy of the discriminatory private schools, which in turn facilitated "white flight" from the public schools, in violation of their children's right to an equal education. The Court denied standing for a number of reasons, including the contention that it was merely "speculative" whether withdrawal of tax-exempt status would, in fact, lead to greater racial integration of the public schools. Thus, the plaintiffs were denied the remedy they sought, not because they were not legally entitled to it, but rather because of a judgment by the Court that it really wasn't in the plaintiffs' interests.

Massachusetts v. EPA is similar. Nobody believes that EPA regulation of greenhouse gas emissions from motor vehicles will, by itself, put an end to global warming, but the plaintiffs argue that it will make at least some difference. Yet during the argument, the Justices peppered Mr. Milkey with questions suggesting that because other factors--such as continued industrialization in China--could exacerbate global warming, EPA regulation of motor vehicle emissions would yield only "speculative" benefits.

Here too, Mr. Milkey heroically argued that every little bit counts. He contended, in other words, that he had shown a likelihood of redress. But the deeper question is why he even should have had to make such a showing. If a plaintiff can show that a defendant's unlawful conduct is injuring him, why shouldn't the plaintiff be entitled to have a court order the defendant to stop the unlawful conduct? The redressability requirement of standing doctrine imposes an unnecessary hurdle on plaintiffs by assuming, unrealistically, that plaintiffs will often ask for relief that does not in any way benefit them.

The Best Result: Dismiss the Standing Doctrine Itself

Conservatives like to complain that liberals read their own political preferences into the Constitution, but when it comes to standing doctrine, the shoe is on the other foot. Here the Court's conservatives have been the ones reading their preferences into the Constitution: in this instance, a preference for keeping civil rights and environmental cases out of the federal courts.

To be sure, since the days of President George Washington, the case-or-controversy language of Article III has been understood to forbid advisory opinions in the literal sense: The Justices refused to give Washington legal advice about a treaty. Yet it is only since the early 1970s that an increasingly conservative Supreme Court has located in the case-or-controversy requirement a set of rigid limits on the jurisdiction of federal courts.

In addition to its suspect pedigree, the standing doctrine has been used in ways that suggest ideological bias. Even as the Court has denied standing to civil rights plaintiffs in cases like Allen v. Wright, it has granted standing to white plaintiffs challenging affirmative action programs. Yet in many of these cases, the plaintiff has been unable to show that a favorable ruling would benefit him or her. For example, in some of the education cases, it was clear that the white applicant would have been rejected even if the defendant university used purely race-neutral policies. No problem, the Court, has said: An order directing the defendant to halt its affirmative action program is permissible because it would redress the denial of an opportunity to compete for admission on an equal footing. But nowhere has the Court explained why the remedy in other cases cannot be recharacterized in such an "opportunistic" fashion. Why not treat the remedy sought in Massachusetts v. EPA as an opportunity to preserve coastline?

Perhaps most damning of all, the standing doctrine does not even accomplish its stated ends, as Massachusetts v. EPA well illustrates. In or230x230der to determine whether the plaintiffs face a particularized and imminent injury that a favorable ruling will likely redress, the Justices must grapple with a key question the standing doctrine supposedly avoids: whether, and to what extent, the EPA's failure to regulate greenhouse gas emissions from motor vehicles contributes to global warming. The Court's energy would be better spent addressing the merits of the case directly.

The Court's rigid standing doctrine simply gets in the way of addressing the real issues. When it comes to global warming, we have had far too much of that approach already.

Michael C. Dorf is the Isidore & Seville Sulzbacher Professor of Law at Columbia University. He is the author of No Litmus Test: Law and Politics in the Twenty-First Century and he blogs at www.michaeldorf.org.